medium lens adapter
 

My first static medium lens adapter is while without a condenser:

Mamiya 80mm 2.8 -> GG -> HV20

http://filezzz.net/3465477

Hi I can't make it run
can you post a frame or the same file in another format?
I'm very curious to see it

It a file in a format .mov is coded by Apple Intermediate.
I will prepare separate shots in a .JPEG format and will code films by H264.

These files in any way were not processed. Only diminished from 1920 to 1280. I have three sets of condenser lenses with focal distance 67, 120 and 150mm.
They must will be equalize light in a shot. I will write in the near time, what correspond better.

http://rapidshare.com/files/57925455/belog4.mov
http://rapidshare.com/files/57937872/belog4-1.jpg
http://rapidshare.com/files/57937873/belog4-2.jpg

http://rapidshare.com/files/57927619/belog5.mov
http://rapidshare.com/files/57937874/belog5-1.jpg
http://rapidshare.com/files/57937875/belog5-2.jpg

http://rapidshare.com/files/57933109/belog6.mov
http://rapidshare.com/files/57937876/belog6-1.jpg
http://rapidshare.com/files/57937877/belog6-2.jpg

very nice good work :-)
let we know what is the best condenser combination

the best choice is 150mm PCX lenses:

Mamiya 645 -> (] -> GG -> [) -> HV20

such combination takes away vignetting, quite small barrel distortion (but it is property of every consumer lens) and no chromatic aberration fully.

I will make new movies after a couple of days, now very busy

ok good
but why have you put a pcx between lens and gg?
to avoid barrel distortion you can setup like this:
Mamiya 645 -> GG -> [) -> (] -> HV20

what have you use as static gg? 1000grit aluminum oxide self made?

On a theory I also thought so, but practice showed other result. I tried all of combinations and discovered that it looked better.
I use home-made a wax GG (diameter 82mm). Working field 55x55mm. It is far better, than grinded glass - no visual grain.

cool I'm building one myself with mamiya 645 lens
I've got 80 2.8 and 1.9 45 2.8 lens :-)
that's why I'm interested
what kind of wax did you use? have you got a link?
for now many thanks for your post!

I expended about 3 months in experiments with different waxes. A lots of attempts. The best is an alloy of paraffin and beeswax 9:1. The pure paraffin is for a sale in a pharmacy. I purchased a beeswax here:
http://www.onestopcandle.com/Merchan...tegory_Code=CA

you're a master
many thanks
Matteo

:D write about your successes

Adapter with condenser:
http://www.dvinfo.net/conf/attachmen...0&d=1191516559
new footage:
http://rapidshare.com/files/60253781/dovgan5.mov

Hi Svyatoslav good job but I think is much better and impressive the image produced by the wax gg alone ...no condenser (are sharper)
Are the condenser of good quality or not ?
have you try to put only the 150 condenser this way
Mamiya 645 -> GG -> [) -> HV20
the inversion point of the lens in the hv20 have to be put at 150mm from the condenser so 140 more or less (this way you achieve all the light that come on the ground glass)
I've got a nikon d screen and the condenser is only on one side
by the way...there is not a lot of vignetting in the gg alone to adjust
:D

for barrel distorsion take a look at this
http://www.dvinfo.net/conf/showthread.php?t=50884

it is unbelievable...
there is not a grain, no vignette, no distortion, no aberrations, very sharply!
Matteo, many THANX :)
Mamiya 645/80/2.8 => 63mm => wax GG => 12mm => PCX Lens D70/FL67 [)=> 66mm => HV20
a very good bokeh.
I would like to thank Wayne and Dennis for their reports

:-) you're welcome

post some good result!
I'm waiting for the beeswax
I've already got the pure paraffin to make the alloy 9/10paraffin +1/10beeswax
like you told me

so many thanks you too

It is the not last version of my adapter, but "coming soon".
I specially left edges in sight
http://rapidshare.com/files/61138040/belog2.mov
http://rapidshare.com/files/61138041/belog3.mov
http://rapidshare.com/files/61138042/belog4.mov
It is very difficult to catch a sharpness without an additional monitor.
2.8 for a medium lens, it that 1.4 for 35mm

we're on the right way! awesome result and with a static adapter!
very good!
one question: I've see that the melting point of the paraffin is 50° more or less
did you encounter some trouble? using it in a close box!? (the adapter?)

I am sure that it is a not problem. when you will do an alloy in practice, you will understand, what high temperature is needed for melting. Although, if you will create such environment, your camcorder will break too :)

Hi Svyatoslav any news!?
I've seen that to be perfect the image is sharp from corner to corner, in the center is ok but in the corner there a little purple chroma aberration
have you solved it in the final release?
I think that cause the bigger image of a medium format lens on the gg we need an achromat instead a condenser!
I have taken lenses from http://www.surplusshed.com/
and http://www.anchoroptics.com/catalog/product.cfm?id=257
but for achromat the larger they have in stock is D60 F136.5
did you think is enough D60 or we need D70 lens?
did you know a cheaper lens seller?
:-)

The achromat from dennis wood, at 72mm in diameter, solved my problems with soft edges and chromatic abberation. I also use it with my mid format adapter using mamiya 645 lenses. The set up is usually ok with 80mm f1.9 and 150mm/ With the wider 45mm there is a slight vignette which will disappear when you slightly adjust your zoom. I suggest you go for |Dennis wood's high grade achromat.

Ted

Ted did you use the dennis wood's achromat in front of the camera lens
or like I suggest?
Mamiya 645/80/2.8 => 63mm => wax GG => space => Achromat Lens [)=> space => HV20 (camera)

Would you able to explain how you go about making a Wax based GG? A tutorial perhaps?

:))) Matteo, I already got this achromat from Surplusshed, but did not yet test.
It seems to me, that it stands not nearly expensive, as compared to other.
I buy some lenses here www.anchoroptics.com (I tested their diffusion films and glasses - very bad).
I was most disturbed by vignetting and sharpness. Condenser worked out these problems.
You are right, aberration is on edges and I showed them specially. But I planned to avoid them, simply doing zoom.
It is balance: if to approach a condenser to gg, less aberration, but anymore barrel distortion. And vice versa.
Practically I plan to utillize an adapter for commercials on broadcasting tv and musical clips on dvd. It's only PAL: 720x576 4:2:0 and my adapter fully arranges me. But, I would like to do an adapter better, than Movietube. I think it is real, as they use an static adapter gg24x18mm and complicated flip-system.
If I will be able to clean corner aberrations, it will be ideal adapter :) And I'll shoot via HDMI 4:2:2 http://www.dvinfo.net/conf/showthread.php?t=104431. I do supporting rails and own system of remote Follow Focus now.

Thanx, Ted. Achromat is simply high-quality magnification lens. May be it simply increases central part, where are not distortions? Achromat is not needed in an mid lens adapter as magnification lens.
If achromat is a good condenser, I will use it certainly .

Louis, unfortunately, I do not know English so well, clearly to explain.
I used two new photo filters Marumi 82mm (I experimented with old filters 67mm).
Gaskets from cook foil in four places.
Glasses must be very clean. We lay them in a pan and sprinkle with a wax. Heating is needed very fluently. The basic problem is bubbles. We delete their by shaking.

Matteo,

In my setup, the achromat sits between the camera lens and the ground glass.
The mid format lens cast a big image already on the gg, i set my zoom distance in order for me to pick up the gg image that measures 36mm by 24mm.
This is the optimum size for most of my lenses. A larger image size will show vignette on the corners. for my wider lens ther is a slight, negligible for me, vignette.
The mamiya lens to gg distance is exactly the same flange depth as if it were on the mamiya body. I can use the focus distance markings on the lens accurately.

Ted

Thanks Ted and Svyatoslav
-Louis take a look at this tutorial http://members.chello.nl/a.schultzev...nburg/wax3.htm

Svyatoslav,

I have experimented from magnifying lens to macros, close-up filters before finally deciding on an achromat.
Without an achromat the camera lens will have to move so far back to to focus on the gg. with close up and macros i was able to shorten the length of the setup but the chromatic abberation on the sides of the image(purple and green fringe) is exaggerated. the achromat acts as a close up but also corrects the CA.
Eventually your experimentation will lead you to this conclusion.

Ted

threads on my adapter are here

http://www.dvinfo.net/conf/showthread.php?t=62837

http://www.dvinfo.net/conf/showthread.php?t=102779

hope this helps to shorten your process.

I appreciate your efforts to explain the process.You results are impressive.The most natural looking adapter I've seen yet.



Thanks Matteo

Thanx. I can not write tutorial, but if you will do such adapter, I will in detail answer your questions. Possibly you will do better and will tell me :)

While the small problem of aberration remains. The use of achromat does not help. Achromat well operates as a close-up lens, but does not work as a condenser.
It may be necessary to utillize other. I can not find achromat like D70-80mm and FL60-70mm.

maybe I've solved the lens aberration!
I've seen that the problem is the spherical aberration of the lens
to solve that we have to use another type of condenser
the aspherical pcx lens
for standard adapter the image is so small that a normal pcx is enough :-)
here is the link from anchor optic
http://www.anchoroptics.com/catalog/...34&s=type&d=a#

note that not all the size have the aspherical type
AX20566 73.5 52 PCX 1 ASPHERIC $11.50
maybe that work

also these link :
http://www.alignoptics.com/aspheric-...er-lenses.html
http://www.edmundoptics.com/onlineca...productID=2454

look at the picture and also this link:
http://www.jenoptik.com/cps/rde/xchg...s.xsl/4029.htm

p.s. I also haven't found big and cheap acromat lens :-(

Recently I purchased a pair
PRECISION PCX ASPHERIC LENS 65MM DIA, 53MM FL from Surplus
There indeed are no questions about CA.
But very strong barrel, if to use only one.
And if to use both [)l(] or (]l[), nothing is visible :(

.... :-(
and using the 120fl pcx
color aberretion is the same or less!?
Mamiya 645/80/2.8 => 63mm => wax GG => 12mm => PCX Lens D70/FL120 [)=> +-120mm => HV20

I have D75/FL120 and D76/FL130.
Yes, CA is less, but yet noticeable.
Also there is substantial vignette.
I search a compromise between vignette, CA and barrel distortion now.
Maybe like this:
Mamiya 645/80/2.8 => 63mm => wax GG => 7mm => PCX Lens D70/FL67 [)=> +-100mm => HV20

Looks not beautifully, but it is a project version

:-) looks good!

I've ordered this lens ...I'll tell you if it works
http://www.surplusshed.com/pages/item/l3788.html

Just did amateur video for my friend. Taken off as early as September. It have not any aesthetic value. Only demonstrates possibilities of my old static adapter
Mamiya 80 f2.8 => gg => PCX => hv20
http://www.artmaster.kiev.ua/media/HV20_final.mov